1. Field of the Invention
The present invention generally relates to a stacked type chip package structure, and more particularly, to a stacked type chip package structure having a RF (radio frequency) chip.
2. Description of Related Art
In accordance with the highly advanced telecommunication in our modern society, the chip structure has to be developed in response to the influence of electronic equipment being digitized, network applicable, locally connectable, and humanized for the electronic equipment. To achieve the above objectives, high processing speed, multi-functional, integration, small volume, light weight, and low cost are all required. Nowadays, many electronic devices must use RF chips with other kinds of chips, such as RF chip in conjunction with digital IC, digital signal processor (DSP), or base band (BB) chip, for achieving the purposes of small volume and high processing speed. However, since RF chips belong to high frequency chips, electromagnetic shielding is required in order to avoid signal interference.
FIG. 1 is a schematic cross-section view showing a conventional stacked type chip package structure. Referring to FIG. 1, a conventional stacked type chip package structure 100 comprises a carrier 110, a first chip 120, a second chip 130, and a metallic plate 140. The carrier 110 has an upper surface 112 and a lower surface 114. The first chip 120 is disposed on the upper surface 112 of the carrier 110, and is electrically connected thereto. The second chip 130, which is disposed above the first chip 120, is a RF chip, and is electrically connected to the carrier 110. The metallic plate 140 is sandwiched between the first chip 120 and the second chip 130, and is electrically connected to a ground 150, for preventing the RF chip from signal interference. However, the metallic plate 140 between the first chip 120 and the second chip 130 may cause an increase in total thickness of the stacked type chip package structure 100, and this may not satisfy the demands for small volume and light weight of electronic devices.